Safety jack base



June 28, 1949. c, C JR 2,474,725

SAFETY JACK BASE Filed Aug. 6, 1945' Patented June 28, 1949 UNITEDSTATES PATENT OFFICE SAFETY JACK BASE Harry 0. Clark, Jr., Belvidere,Ill.

Application August 6, 1945, Serial No. 609,275

3 Claims.

This invention relates to lifting jacks, and more particularly to a basestructure for a lifting jack.

A main object of the invention is to provide a novel and improved basestructure for a lifting jack which insures safety in using the jack tolift vehicles on an inclined road surface.

A further object of the invention is to provide an improved jack basehaving a plurality of jack mountings corresponding to various degrees ofinclination of the road surface so that the jack may be mounted in asafe manner on the base for a wide range of angular inclinations of theroad surface.

Further objects and advantages of the invention will appear from thefollowing description and claims, and from the accompanying drawings,wherein:

Figure 1 is an elevational view of a jack mounted on a jack base made inaccordance with this invention as employed to lift a vehicle on an Hinclined road surface.

Figure 2 is a plan view of the jack base employed in Figure 1.

In lifting a vehicle to change a tire on a road surface of substantialinclination, the conventional jack base provides a very unstable andunsafe support since the lifting force is applied at right angles to thebase and the weight of the vehicle produces a moment tending to tip thejack over on its lowermost edge. It is a main purpose of this inventionto provide a jack base which is arranged to receive the lower end of aconventional jack shaft and to support the shaft in substantiallyvertical position where the road surface is inclined.

Referring to the drawings, the base comprises leg members ll, l2 and I3connected rigidly together at a central junction point M and spacedangularly approximately 120, said leg members lying in a common plane.Integrally formed therewith, as by welding, and projecting upwardlybetween the adjacent leg members are socket members [5, l6 and I1, eachbeing adapted to receive the lower end of the shaft is of a jack l9 andto rigidly support the jack with respect to the leg members. The socketmembers 15, I6 and I! have their axes at different angles with respectto the plane of the leg members. Thus, socket member l may be at anangle of 90 with respect to the base plane, socket member I! may be atan angle of 85, and socket member 16 may be at an angle of 70 withrespect to the base. For a horizontal road surface socket I5 isemployed, for a slight inclination socket I1 is em ployed, and for arelatively steep inclination socket I6 is employed, whereby the liftingforce of the jack may be applied in a substantially wertical directionto insure safety in the use of the jack.

The leg members l5, I6 and I! are of substantial length to providestability under all required conditions of use.

Although shown as having three leg members and three socket members, anydesired number of leg members and socket members may be employed in thebase within the contemplation of this invention.

While a specific embodiment of a safety jack base has been disclosed inthe foregoing description, it will be understood that variousmodifications within the spirit of the invention may occur to thoseskilled in the art. Therefore, it is intended that no limitations beplaced on the invention other than as defined by the scope of theappended claims.

What is claimed is:

1. A jack base comprising a plurality of radially disposed leg membersof substantial length rigidly joined together, and a plurality of socketelements rigidly secured to the base adjacent the junction point of saidlegs, the axes of said socket elements being at different angles withrespect to the base.

2. A jack base comprising three leg members rigidly joined together attheir inner end portions to define a Y-shaped structure, said legmembers being of substantial length, and a plurality of socket membersrigidly secured between adjacent leg members adjacent the junction pointthereof, one of said socket members being at an angle of 90 to the planeof said base and the others having their axes at different angles withrespect to the base, each socket member being adapted to receive thelower end of a jack shaft and to hold said shaft rigidly with respect tothe base.

3. The structure of claim 2, and wherein there are three socket members,the one socket member being at the stated angle of 90, a second being atan angle of approximately 85 and the third being at an angle ofapproximately to the base. I

HARRY C. CLARK, JR.

REFERENCES CITED The following references are of record in the file ofthis patent:

